1. Field of the Invention
The invention relates to the field of systems of transactions using microcircuit circuits and, more particularly, to a method and to a corresponding device for the management of transactions, using such cards.
2. Description of the Prior Art
Microcircuit cards are conventionally used in systems of banking transactions. For transactions of this type, the use of the card in a reader makes it necessary to present a confidential code, which is the bearer's own code, to this reader, authorizing the transaction to be carried out once it involves a sum of money. In other applications, this confidential code may not have to be presented, notably if these applications do not bring the microcircuit into play and if the only operation used is the reading of a magnetic track on the card. However, at present and in general, once the required application uses the microcircuit, notably to record a transaction in a memory space designed for this purpose, the bearer's code is presented systematically, irrespectively of the sum of money involved in the transaction.
A system such as this enjoys total security but obviously has the drawback of being cumbersome and tedious to use when the sum involved in the transactions is small: although the presenting of the confidential code can be envisaged for large sums of money and although we can appreciate the security that must surround these large sums, it would appear that the systematic presenting of the confidential code for purchases involving small sums is disproportionate to the corresponding risk.
Consequently, for the multiple-use cards that are likely to be developed in the future, notably for credit cards, telephone cards etc., it would be appropriate to have different ways of processing transactions involving large sums of money and those involving only small sums.